Expression patterns of killer cell immunoglobulin-like receptors (KIR) of NK-cell and T-cell subsets in Old World monkeys.

The expression of killer cell immunoglobulin-like receptors (KIR) on lymphocytes of rhesus macaques and other Old World monkeys was unknown so far. We used our recently established monoclonal anti-rhesus macaque KIR antibodies in multicolour flow cytometry for phenotypic characterization of KIR protein expression on natural killer (NK) cells and T cell subsets of rhesus macaques, cynomolgus macaques, hamadryas baboons, and African green monkeys. Similar to human KIR, we found clonal expression patterns of KIR on NK and T cell subsets in rhesus macaques and differences between individuals using pan-KIR3D antibody 1C7 and antibodies specific for single KIR. Similar results were obtained with lymphocytes from the other studied species. Notably, African green monkeys show only a low frequency of KIR3D expressed on CD8+ αβT cells. Contrasting human NK cells are KIR-positive CD56bright NK cells and frequencies of KIR-expressing NK cells that are independent of the presence of their cognate MHC class I ligands in rhesus macaques. Interestingly, the frequency of KIR-expressing cells and the expression strength of KIR3D are correlated in γδ T cells of rhesus macaques and CD8+ αβT cells of baboons

Asynchronous Onset of Clinical Disease in BSE-Infected Macaques

To estimate the effect of the variability of prion disease onset on primary bovine spongiform encephalopathy transmission to humans, we studied 6 cynomolgus macaques. The preclinical incubation period was significantly prolonged in 2 animals, implying that onset of variant Creutzfeldt-Jacob disease in humans could be more diverse than previously expected

Analysis of KIR3D protein expression on rhesus macaque T cell subsets.

<p>(A) CD8 αβ T cells were analysed for frequency of KIR expression (left panel), mean fluorescence intensity (antibody 1C7) (middle panel), linear regression analysis of KIR frequency and MFI (right panel). (B) γδ T cells were analysed for frequency of KIR expression (left panel), mean fluorescence intensity (antibody 1C7) (middle panel), linear regression analysis of KIR frequency and MFI (right panel). (C) CD4 αβ T cells were analysed for frequency of KIR expression (left panel), mean fluorescence intensity (antibody 1C7) (middle panel), linear regression analysis of KIR frequency and MFI (right panel). Antibody 2H5 detects KIR3DL05, whereas antibody 2H9 detects KIR3DS05 and KIR3DLW03 in animal 2425 and only KIR3DS05 in animals 2136, 2146, 2405, 14225, and 14218, and only KIR3DLW03 in animal 14229 according to <i>KIR</i> genotyping.</p

Gating strategy for rhesus macaque PBMCs.

<p>(A) After gating on monettes (FSC-A, FSC-H) and lymphocytes (SSC-A, FSC-A), CD14-positive cells and CD20⁺ (B cells) were excluded. (B) NK cells and T cells were identified based on NKG2A/C, CD16 and CD3 expression. CD16-positive mDCs were excluded by gating on CD8-positive CD16-positive cells (CD16⁺ exact gate). A Boolean gate was subsequently produced to display the NK cells. (C) The CD3-positive cells were distinguished based on γδ TCR, CD4, and CD8 expression.</p

KIR3D protein expression on NK cells and CD8⁺ T cells in other Old World monkeys.

<p>Antibody 1C7 was used to determine the frequencies of KIR3D-positive cells (left panels), MFI (middle panels), and linear regression analysis (right panel) in (A) cynomolgus macaques (n = 4), (B) hamadryas baboons (n = 4), and (C) African green monkeys (n = 4).</p

Analysis of KIR3D protein expression on rhesus macaque NK cell subsets.

<p>NK cells were analysed for CD56, CD16 and pan-KIR3D antibody 1C7. Results obtained from rhesus macaque individual Gerdi (2136) are shown. All three NK cell subsets express KIR3D proteins: CD56⁺CD16⁻ (34.1%), CD56⁻CD16⁻ (33.0%), CD56⁻CD16⁺ (54.8%).</p

Identified <i>MHC class I</i> and <i>KIR</i> gene transcripts.

a<p>MHC class I proteins that are known to interact with KIR3DL05 are shown in bold type.</p>b<p>% KIR3DL05-positive NK cells were determined with specific antibody 2H5; mean flourescence intensity (MFI) is indicated.</p>c<p>in those cases where only a single <i>3DL05</i> sequence was found, this might be either due to <i>3DL05</i> being present on only one chromosome (1 gene copy) or 3DL05 being present on both chromosomes (2 gene copies, but homozygosity).</p

Analysis of KIR3D protein expression on rhesus macaque NK cells.

<p>(A) % KIR-positive NK cells and (B) mean fluorescence intensity (MFI) are shown for antibodies 1C7 (pan-KIR3D), 2H5 (KIR3DL05), and 2H9 (KIR3DLW03, KIR3DS05) for the indicated rhesus macaques. (C) Linear regression analysis of % KIR-positive NK cells and mean fluorescence intensity is shown for antibody 1C7. (D) Frequencies of KIR3D-positive NK cells (antibody 1C7) were followed in three animals over a period of 12 months in 4-month-intervalls. Antibody 2H9 detects KIR3DS05 and KIR3DLW03 in animal 2425 and only KIR3DS05 in animals 2136, 2146, 2405, 14225, and 14218, and only KIR3DLW03 in animal 14229 according to <i>KIR</i> genotyping (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0064936#pone-0064936-t001" target="_blank">Table 1</a>).</p